Controller for electric motors.



, d HIHALL. CONTROLLER FOR ELECTRIC MOTORS.

APPLICATION FILED 0GT.16,1912.

' 1,084,698. Patented Jan. 20, 1914.

2 'SHBETSSHEET 1.

IWITNEKSSTSES 11v VE'N TOR.

J/MM- 4 'ZF./k- M A TTOR/VE Y.

J. H. HALL.

CONTROLLER FOR ELECTRIC MOTORS.

APPLICATION FILED 0CT.16, 1912v 1,084,698. Patented Jan. 20, 1914.

2 SHEETS-"SHEET 2.

WITNESSES: 11v VLN TOR. 6 V M v /%M I fiTORNE y.

. 1 .osacos.

prormnents in Controllers for cuit has diminished to a certain value.

UNITED sirnrrns PATENT onnion.

JAY H, HALL. OF CLEVELAND, OHIO, ASSIGNOR TO THE ELECTRIC CONTROLLER ANDMANUFACTURING COMPANY, OF CLEVELAND, OHIO, A'CORPORATION OF OHIO.

CONTROLLER Specification of Letters Patent.

FOR ELECTRIC MOTORS.

Patented Jan. 2'0, 1914..

Application filed October 16, 1912. Serial No. 726,030.

To all whom it may; concern:

Be it known that I, JAY H. HALL, a citizen of the United States,residing at Cleveland, in the county of (luyahoga and State of Ohio,have inrented new anduseful 'Im- Electric Motors,ot which the followingis a specification.

My invention relates to controllers for electric motors, particularlythattype of controller in which ,magnetically operated switches are usedto make the proper connections for starting a motor and safely bringingit up to speed.

My invention relates more specifically to an arrangement whereby themotor is first connected to the supply circuit through a transformer andthen connected directly to the supply circuit.

One of the objects of my invent-ion is to prevent. the connection of themotor directly to the supply circuit until the current in the motor hasdiminished to' a certain value while it is connqzted through thetransformer.

Another objcct'is to effect the change from the starting connection tothe running connection without the use of the numerous auxiliarycontacts and relays, as heretofore.

in carrying out my i vention I provide a magnetically operated startingswitch for first connecting the motor to the supply circuit through thetransformer, and a second magnetically operated running switch forconnecting the motor directly to the supply circuit. The circuit of thewinding of the starting switch is controlled by a current limit relay,so that the winding is not. deenergized until the current in the motorcir- The relay has its winding energized by current prop rtional to thattaken by the motor in starting. The relay in operating not only opensthe circuit of the starting switchwinding, but short circuits aresistance in the circuit of the running switch winding. As soon as thestarting switch opens the circuit of the running switch winding iscompleted and the running switch immediately closes, connecting themotor directly to the supply circuit, whereupon it ac elerates to normalspeed. I prefer to place the operating winding of the-relay in thestarting circuit of the motor so that it will be deenergized during therunning period of the motor, and 1 provide means for delaying the returnof the relay to its normal position until the running switch has closedits contacts.

Other objects of my invention will hereinafter appear.'-

Referringto the Figures 1 and 2 are wiring diagrams show ing two"different arrangements embodying my invention.

In these drawings 1 is an electromotor supplied with current through theswitch 2. In Fig. 1 a transformer L is connected to the supply circuitthrough the contacts of the switch and the motor J taps on thetransformer for starting thro the contacts of the switch 6. After the intor has accelerated to a point where the current in the motor circuithas diminished to a certain value. the contacts of the switcl'i 6 areopened and the switch 12 is then closed, connecting the motor throughits contacts directly to the supply circuit. The relay which controlsthe operation of the switches, has its winding connected between themotor accompanying drawings,

and the transformer, but proper operation can be secured by connectingthe relay winch mg between the transformer and the supply circuit. ordirectly in the motor circuit itself.

The relay 9 is that type of relay shown in rlastwoods Patent No.1,040,292, which is arranged to remain in its unoperated position whenthe currentin .the winding is above a predetermined value, and be movedto the operated position by its winding when the current thereindiminishes to that value.

I have placed oppositethis relay the legend Lock open, to indicate thistype of switch. Upon closure of the master switch 7, the windings 5and'ti of the switches 5 and 6 are energized by the following circuit:from the supply circuit through the master switch 7, and the contacts 12which are closed when the switch 19. is opened to the point 13, wherethe circuit divides, one branch passing through the winding 5 to theother 'side of the supply circuit, and the other branch passing throughthe contacts 9" which are normally closed. when the winding of the relay9 is denergined or unoperated, and through the winding 6 to'the otherside of the supply circuit. The switches and 6 immediately close theircontacts, and current is supplied to the motor thronghthe windings ofthe transformer 4. Prior to the closure of the switch 6 current flowsthrough iii? ' and deenergizes the relay winding 9.

the winding 12 of the switch 12, the resistance 11, and the contacts 6of the switch (3; but the current in the winding 12, limited by theresistance 11, is not sutlicient to close the switch 12. If the currentwhich flows through the operating winding of the relay 9 exceeds apredetermined Yalue, it locks the relay in its normal position as shownin the drawing; and as the motor increases its speed and the current inthe relay winding diminishes, the relay operates to open the contacts 9andclose the contacts 9. The holding winding 9 on the relay is connectedto the supply circuit through the contacts of the switch and is en zedupon the closure of this switch, but it has not sufiicient energy tocause the relay to operate. "t will however, hold the relay in itsoperated position after it has been operated by the winding As soon asthe relay contacts 9 are opened, the n ding 6 deenergized, and theswitch opens and disconnects the motor from the transformer The relay,however, remains in its operated position, since the holding winding 9is still energized through the contacts ofthe switch 5. Upon the returnof the switch 6 to its open position, its contacts 6 are closed therehyestablishing a circuit through the winding 12*- oi the switch 12 asfollows: from the supply circuit, through the master switch .7, thewinding 12, through the contacts '9 of the relay, and the contacts 6 tothe other side of'the supply circuit. The switch 12 immediately closesand connects the motor through its contacts directly to the supplycircuit, and the motor accelerates to its normal speed. The closure ofthe switch 12 opens its auxiliary contacts 12, thereby deenergizing thewinding 5, causing the switch 5 to open and disconnect the transformerfrom the supply circuit. The holding winding 9 of the relay is nowdecnergized, allowing the relay to return to its normal position,opening its contacts c and e resistance 11in the circuit of inserting th12, but the current in the the winding ing is not sul'ficiently reducedthereby to cause the switch 12 to open. The relay closes ts contacts 9",but the winding 6 does not become QDBI' 'lZCLl since its circuit is nowa, 7 rr- I opened at the contacts r2. lo stop the motor the switch 7 iso ened thereh deener 'ia 7 J 2:

111g the winding 12 opens its contacts, discon sets the motor l l l l Il I I wind- 12, whereupon the switch from the supply circuit, aid closesits con.'

tacts 12", placing for restarting the the master switch In Fig, 2, thecontacts of the switch 8 connect the transformer 4: to the supplycircuit, and also connect on the transformer.

the controller in position motor upon the closure of Upon closure of thethe motor to the taps possess switch 2 a circuit is established throughthe winding 3, which goes from one side of the supply circuit throughthe switch 12, the contacts 9* of the relay, and the winding 3 to theother side of the supply circuit. A circuit is also established ing 12",the resistance 11, and the contacts 3 but the resistance 11 limits thecurrent in this circuit to a value which is not suflicient to operatethe switch 12." The switch' 3 by contacts, thereby connecting thetransform 1' 4- to the supply circuit through the contacts 3" and 3and-the motor to the taps on the transformer through the contacts 3 and3, The relay winding 9 current which passes through the "transformer,and if the current in this winding is above a predetermined value, therelay, which is ofthe same type as the relay shown in Fig. 1, will lockits movable its initial position until the current is rc duced to thatvalue, whereupon the contacts 9 will be opened and the contacts 9 willbe closed. The opening of the contacts 9* deenergizes the winding 8, theswitch 3 opens its contacts and disconnects the motor from thetransformer, Upon the closure of the contacts 3 the winding 12 is fullyenergized, the limiting resistance 11 being short-circuitcd by the retacts 9. he switch 12 now closes its contacts, connecting the motordirectly to the supply circuit, whereupon the motor accelerates to itsnormal speed. The switch 12 in operating opens the contacts 12preventing the flow of current through the winding 3 upon the closure ofthe relay contacts 9 when the relay returns to its initial position. inorder to prevent the relay from opening its contacts 9 inunc- 105diately upon the decnergization of its operating winding by the openingof the switch 3, I provide a dashpot 9 for causing the relay to slowlyreturn to its initial position, thereby giving the switch 12 ample 110of the contacts are once closed.

troller in a position for the next operation 125 in starting the motor.

I claiml. The combination of an induction motor,

through the windthe energy of the winding 3, closes its,

is energized by the member in 35 whereupon 9o lay conthereby the winding12 the switch will 1;

opened, 1123 a supply circuit, a transformer, switch for connecting themotor to the supply circuit through the transformer, an operatingwinding therefor, contacts in series with the winding, and an operatingcoil for the contacts energized by current through the motor.

2. The combination of an induction motor, a supply circuit,a'transformer, a starting switch for connecting the motor to the supplycircuit through the transformer, a running'switch for connecting themotor directly to the supply circuit, operating windings for the saidswitches, a resistance in series with the running switch winding, switchcontacts for short circuiting the resistance, and an operating windingfor the switch contacts energized by current through the motor.

3. The combination of an induction motor, a supply circuit, atransformer, a starting switch for connecting the motor to the sup plycircuit through the transformer, a running switch for connecting themotor directly to the supply circuit, operating windings for the saidswitches, switch contacts in series with the windings, and an operatingwinding for the switch contacts energized by current through the motor.

The combination of aninductiou motor, a supply circuit, a transformer, astarting switch'for connecting the motor to the supply circuit throughthe transformer, a running switch for connecting the motor di rectiy tothe supply circuit, operating windings for the said switches, contactsin series with each winding controlled by the other winding, andcontacts in series with each winding operated by a winding energized bythe motor current.

o. in an induction motor controller, in com liiation, starting switch, arunning switch, operating windings therefor, a relay having windingenergized by current in the motor circuit upon the closure of thestarting switch, contacts in the circuit of the starting switch windingnormally closed by the relay, normally open contacts in the circuit ofthe running switch winding closable by the relay when operated, meansfor deenergizing the relay winding before the closure of the runningswitch, and means for preventing the immediate return of the relay toits normal position when its winding is deenergized.

6. The combination of an induction motor, a supply circuit, atransformer, magnetically-operated contacts for connecting the motor tothe supply circuit through the t unsformer, means automatically operatedfor opening the said contacts only when the currenttaken by the motor instarting is below a certain value, magnetically operated contacts vforconnecting the motor directly to a starting the supply circuit,

l t l i l t and means controlled by and by the opening of the, causingthe closure of the the motor current first contacts for second contacts.

7. In combination, an induction motor, a supply circuit, a transformer,magneticallyoperated contacts for first connecting the motor to thesupply circuit through the transformer and then connecting the motordirectly to the supply circuit, a relay having, normally closed contactsfor con rolling ll"! 15 connection of the motor to the transformer, andnormally open contacts for controlling the connection of the motordirectly to the supply circuit, the relay moving its contacts to thciroperated position only when the 30 starting current of the motor isbelow a certain value, and 'means for holding the contacts in theiroperated position after the motor is disconnected from the transformer.

8. In combination, an induction.motor, a as supply circuit, atransformer, magneticallyoperated contacts for first connecting themotor to the supply circuit through the transformer and then connectingthe motor directly to the supply circuit, a relay controlling theconnection of the motor to the transforme and the connection of themotor to the supply circuit, an operating winding therefor energized bycurrent through the transformer, and a holding winding for the relayadapted to be connected to the supply circuit.

9. In coi'nliinalion, an induction motor, a supply circuit, atransformer, magneticallyopcrated contacts for first connecting themotor to the supply circuit through the transformer and then connectingthe motor directly to the supply circuit,'a relay having normally closedcontacts for controlling the connection-20f the motor to thetransformer, and normally open contacts for controlling the connectionof the motor directly to the supply circuit, an operating winding forthe relay energized by current through the transformer, and a holdingwinding for the relay connected to the supply circuit,

10. The combination of an electric motor, a supply circuit, atransformer, a starting switch for connecting the motor to the supplycircuit through the transformer, a running switch for connecting themotor directly to the supply circuit, operating windings for the saidswitches, a relay for causing the opening of the starting switch and theclosing of the running switch, an opcrating winding therefor energizedby current in the motor circuit, means for deenergizing said windingwhen the starting switch opens, and means for holding the relay in itsoperated position until the running switch is closed.

11. T he combination of an electric motor, a supply circuit, atransformer, a starting switch for connecting the motor to the supplycircuit through the transformer, a running switch for connecting themotor directly to the supply circuit, operating Windings for the saidswitches, a relay for causing the opening of the starting switch and theclosing of the running switch, an operating winding therefor energizedby current in the motor circuit, means for deenergizing said Windingwhen the starting switch opens, and a shunt Winding for the relay forholding it in its operated position. The combination of an electricmotor,

a supply circuit, a transformer, a starting s it w for CO1 fleeting themotor to the supongh the transformer, a on for connecting the motorsupply circuit, operating sid switches, relay cons of said windings, anda "y connected in the motor Ill . an electric motor, a tranmormer, astarting cting the motor to the supgh the transformer, a runforconnecting the motor diupply circuit, operating Windswitches, relaycontacts in said windings, and means for relay contacts only when theTeen: In

ction motor controller, in starting switch, a running energized. bycurrent in upon the closure of the ntacts in the circuit of the windingstherefor, a relay starting switch Winding normally closed by the relay,normally open contacts in the circuit of the ru ing switch windingclosable by the relay when operated, means for opening the normallyclosed contacts and for closing the normally open contacts, and meansfor operating the said. contacts from their normal positions only whenthe current in the motor circuit is below a predetermined value.

15. In combination, an induction motor, a supply circuit, a transformer,magneticallyoperated contacts for first connecting the motor to. thesupply circuit through the transformer and then connecting the motordirectly to the supply circuit, a relay con trolling the connection ofthe motor to the transformer and the connection of the motor to thesupply circuit, an operating Winding therefor energized by currentthrough the transformer, and means for preventing the return of therelay to its initial position until after the motor is connecteddirectly to the supply circuit.

1G. In an electric controller, an alternating current motor, a startingswitch, a running switch, operating windings for said switches, meansfor preventing the simultaneous energization of both windings, and meansresponsive to the current through the motor for automatically causingthe sta. ting switch to open and the running switch to close. I

Signed at Cleveland, @hio, this lth day of October, A. D. 1912.

Witnesses R. H. Bnnnm'r', W. M. Dznnnn.

